APLICAÇÃO DE ZINCO NA CULTURA DA SOJA: EFEITOS NA NUTRIÇÃO, QUALIDADE E PRODUTIVIDADE DE GRÃOS

Abstract

Zinc (Zn) is a micronutrient and is essential for the activation of enzymes involved in protein synthesis, hormone regulation and resistance to environmental stress. Given this, it is important to test the hypothesis that the application of Zn to soybean plants promotes an increase in leaf content and grain quality and productivity. Therefore, the objective was to evaluate the effect of fertilization with Zn sulfate on soybean plants, to verify whether the micronutrient promotes an increase in Zn levels in plants and improves grain quality and productivity. The study was conducted in a randomized block experimental design (DBC), with 5 doses of Zn in the soil with 4 replications totaling 20 plots. Zn doses were 0; 2.5; 5; 7.5; 10 kg ha-1, which are supplied through the application of Zn sulfate. Analyzes of Zn content in the leaf, ether extract, protein and grain productivity were carried out. The evaluation of leaf Zn content was carried out at the beginning of the reproductive period, while protein and ether extract analyzes were carried out after harvest. The leaf content of Zn, ether extract and productivity, the presence of Zn significantly influenced it, with a maximum point of 8.45 kg ha-1 of Zn, with an increase of up to 16.77% in relation to the control; 6.5 kg ha-1 of Zn, with an increase of up to 49.07%; and 5.14 kg ha-1 of Zn, an increase of up to 22.27% in relation to the control effect, respectively. The Zn dose of 5.14 kg ha-1 resulted in the highest grain productivity. The doses of 8.45 and 6.5 kg ha-1 of Zn were those that contributed most to the content of Zn in leaves and ether extract.